Cypress CY7C601xx Network Card User Manual


 
CY7C601xx, CY7C602xx
Document 38-16016 Rev. *E Page 11 of 68
9.2.5 Destination Indexed
The result of an instruction using this addressing mode is placed
within either the RAM memory space or the register space.
Operand 1 is added to the X register forming the address that
points to the location of the result. The source for the instruction
is the A register. Arithmetic instructions require two sources; the
second source is the location specified by Operand 1 added with
the X register. Instructions using this addressing mode are two
bytes in length.
Example
9.2.6 Destination Direct Source Immediate
The result of an instruction using this addressing mode is placed
within either the RAM memory space or the register space.
Operand 1 is the address of the result. The source for the
instruction is Operand 2, which is an immediate value. Arithmetic
instructions require two sources; the second source is the
location specified by Operand 1. Instructions using this
addressing mode are three bytes in length.
Examples
9.2.7 Destination Indexed Source Immediate
The result of an instruction using this addressing mode is placed
within either the RAM memory space or the register space.
Operand 1 is added to the X register to form the address of the
result. The source for the instruction is Operand 2, which is an
immediate value. Arithmetic instructions require two sources; the
second source is the location specified by Operand 1 added with
the X register. Instructions using this addressing mode are three
bytes in length.
Examples
9.2.8 Destination Direct Source Direct
The result of an instruction using this addressing mode is placed
within the RAM memory. Operand 1 is the address of the result.
Operand 2 is an address that points to a location in the RAM
memory that is the source for the instruction. This addressing
mode is only valid on the MOV instruction. The instruction using
this addressing mode is three bytes in length.
Example
Table 9-11. Destination Indexed
Opcode Operand 1
Instruction Destination Index
ADD [X+7], A ;In this case, the value in the memory
location at address X+7 is added with the
Accumulator and the result is placed in the
memory location at address X+7. The
Accumulator is unchanged.
Table 9-12. Destination Direct Source Immediate
Opcode Operand 1 Operand 2
Instruction Destination Address Immediate Value
ADD [7], 5 ;In this case, value in the memory location
at address 7 is added to the immediate
value of 5, and the result is placed in the
memory location at address 7.
MOV REG[8], 6 ;In this case, the immediate value of 6 is
moved into the register space location at
address 8.
Table 9-13. Destination Indexed Source Immediate
Opcode Operand 1 Operand 2
Instruction Destination Index Immediate Value
ADD [X+7], 5 ;In this case, the value in the memory
location at address X+7 is added
with the immediate value of 5, and
the result is placed in the memory
location at address X+7.
MOV REG[X+8], 6 ;In this case, the immediate value of
6 is moved into the location in the
register space at address X+8.
Table 9-14. Destination Direct Source Direct
Opcode Operand 1 Operand 2
Instruction Destination Address Source Address
MOV [7], [8] ;In this case, the value in the memory location
at address 8 is moved to the memory location
at address 7.
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